Heat Treatment, Furnaces & Thermal Processing worked example

Hardening Batch Cost at 68% good-part yield after quench cracking: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop good-part yield after quench cracking to 68%, then walk the calculation through step by step. Estimate the total cost of a hardening batch from parts run, per-part hardening rate, post-quench yield, and flat setup or quench-media adders.

The inputs for this scenario

  • Parts hardened per batch: 120 parts (held at the documented default)
  • Hardening processing cost per part: 4.5 $/part (held at the documented default)
  • Good-part yield after quench cracking: 68 % (the input this scenario stresses; the baseline uses 95)
  • Setup and quench media adder per batch: 180 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Batch cost = parts x hardening cost per part x yield% + setup and quench adder.
  • Total hardening batch cost works out to 547 $ at these inputs, and this is the headline figure for the scenario.
  • Hardening cost per pound works out to 4.56 $ / lb at these inputs.
  • Captured hardening cost works out to 367 $ at these inputs.
  • Fixed hardening batch adder works out to 180 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where good-part yield after quench cracking sits at 95% and the headline result is 693 $, this scenario comes in 21.04% below the baseline at 547 $.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to good-part yield after quench cracking, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. The model applies yield as a multiplier on captured cost rather than re-running scrapped parts, so it reflects cost capture for accepted parts, not the full economic loss of remaking rejected ones.

Results at a glance

  • Total hardening batch cost: 547 $ (headline result)
  • Hardening cost per pound: 4.56 $ / lb
  • Captured hardening cost: 367 $
  • Fixed hardening batch adder: 180 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Hardening Batch Cost calculator, set good-part yield after quench cracking to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.